Electrosurgery involves the application of electrical energy to tissue to cut the tissue, coagulate bleeding, or to achieve a combination of cutting and coagulation simultaneously. A high frequency, relatively high powered electrosurgical generator (ESG) supplies the electrical energy, and the energy is applied to the tissue through a blade-like electrode held in a handpiece and manipulated by the surgeon. The blade electrode either contacts the tissue to directly conduct the electrical energy to the tissue, or the blade is slightly spaced from the tissue to create random arcs through the air to the tissue. This type of electrosurgery has been is use for many years, and will be referred to herein as "blade electrosurgery."
To apply the electrical energy to the blade electrode, the ESG is activated or "keyed" by the surgeon depressing a foot switch or by the surgeon depressing finger switches located on the handpiece. When finger switches are used, one switch controls the ESG to supply an energy waveform to achieve cutting, and another switch controls the ESG to supply a different energy waveform to achieve pure coagulation or a blend of cutting and coagulation. The type of waveform delivered in each case is manually selected on the control panel of the ESG. When a foot switch is used, the cutting waveform or the coagulation waveform must be selected for delivery at the control panel of the ESG. A handpiece that separately controls the ESG to obtain both cutting and coagulation effects is desired by many surgeons.
Very recently, a new form of electrosurgery has been introduced. This new form of electrosurgery has been confined to coagulation, and it involves conducting electrical energy to the tissue as arcs in ionized conductive pathways in a flowing stream of inert gas. This type of electrosurgery will be referred to herein as "conductive gas electrocoagulation." Conductive gas electrocoagulation has obtained many significant advancements and improvements in the field of electrosurgery, which prior to its introduction, were impossible and/or unexpected. A more complete description of conductive gas electrocoagulation is available in U.S. Pat. Nos. 4,781,175; 4,901,719; and 4,901,720, all assigned to the assignee of the present invention.
With conductive gas electrocoagulation, the conductive gas jet is delivered to the tissue with a handpiece which the surgeon manipulates. Gas is delivered to the handpiece by a tubing, and an ESG delivers energy to a transfer electrode located within a gas nozzle at the terminal end of the handpiece. The gas flows over the electrode in the nozzle where it is ionized by the electrical potential of the electrode. Electrical energy is transferred from the electrode as arcs in the resulting conductive pathways in the gas flowing to the tissue. In the past, a foot switch has been used to activate the ESG and the flow of gas for conductive gas electrocoagulation.
There are substantial improvements and advantages available from using conductive gas electrocoagulation to coagulate bleeding sites, particularly relatively large, oozing, bleeding sites. However, there are substantial preferences for using blade electrosurgery to cut tissue, primarily because of its ability to simultaneously cut and coagulate. Therefore, many surgeons prefer to use both blade electrosurgery and conductive gas electrocoagulation alternatively during a single surgical procedure. This has required the surgeons to repeatedly change back and forth between the two different handpieces, since cutting and coagulation involves use of a different handpiece than conductive gas electrocoagulation. In addition to using two different types of handpieces, the surgeon may be required to activate each handpiece in a different manner, either by stepping on one foot switch for blade electrosurgery and another foot switch for conductive gas electrocoagulation, or using the foot switch for the conductive gas electrocoagulation and the finger switch on the handpiece for blade electrosurgery.
Changing between the two different handpieces, mentally recognizing that two different activation switches must be operated, and keeping track of both types of equipment, have created additional distractions during surgery which are desireable to avoid. Furthermore, the surgeon has been required to devote additional concentration to the type of equipment rather than to the surgical procedure. Other undesirable factors are also applicable with respect to this situation, and it is against this generally described background that the present invention has resulted.